[PATCH] LSM: add missing hook to do_compat_readv_writev()

This patch addresses a flaw in LSM, where there is no mediation of readv() and writev() in for 32-bit compatible apps using a 64-bit kernel. This bug was discovered and fixed initially in the native readv/writev code [1], but was not fixed in the compat code. Thanks to Al for spotting this one. [1] http://lwn.net/Articles/154282/

James Morris committed 20 years ago

Commit e7edf9c1 parent a090d911 file · +4 −0Browse files

Unified · Split

fs/compat.c+4−0

@@ -1217,6 +1217,10 @@ static ssize_t compat_do_readv_writev(int type, struct file *file, · 1216 unmodified lines
1217	1217	if (ret < 0)
1218	1218	goto out;
1219	1219
	1220	+ ret = security_file_permission(file, type == READ ? MAY_READ:MAY_WRITE);
	1221	+ if (ret)
	1222	+ goto out;
	1223	+
1220	1224	fnv = NULL;
1221	1225	if (type == READ) {
1222	1226	fn = file->f_op->read;